A sudden spate of suicides in the Canadian armed forces has raised urgent questions about care for Afghanistan veterans amid criticism of the government for failing to provide mental health support professionals for soldiers.

Four men have killed themselves in the past two weeks. The latest was Master Corporal Sylvain Lelievre, 46, who was found dead at his military base near Quebec City on Monday. He had served in Afghanistan and in Bosnia during his nearly 30-year career.

The Canadian military is investigating the recent apparent suicides of Warrant Officer Michael McNeil at a base in Ontario, Master Corporal William Elliott in Manitoba and Master Bombardier Travis Halmrast, who was being held on domestic assault charges in an Alberta correctional facility.

According to Canada's department of national defense, nearly 50 soldiers have killed themselves between 2010 and 2012.

The deaths prompted army top brass to release a video message urging soldiers to seek help.

They also generated questions in parliament, where opposition leaders accused the government of a lack of compassion and asked what was being done to address the "unprecedented" death toll.

At its peak, the Canadian detachment in Afghanistan numbered 3,000 soldiers. The Canadian combat role was wound down in 2011, but the country has committed to providing military training assistance to the war-torn country until 2014.

Its experience of suicides mirrors that of the US and UK, where army chiefs have been warned of the rising tide of post-traumatic stress disorder (PTSD).

The illness takes on average 11 years to manifest itself, meaning that countries that had extensive involvement in Iraq and Afghanistan in the first decade of the 21st century can expect a serious outbreak in this the second.

In 2012, more US service members took their own lives than were killed in combat.